over a year ago:
It shows us what he's seeing, that it's completely different to what most of us see. It gets us inside his head, showing that he notices everything.
Interestingly, Roth tried to pick up as little as possible about lie detection, because once you know how to, it's hard to turn it off.

over a year ago:
Saw Roth in Skellig, became obsessed, Googled him, found out about Lie To Me*, realised it wasn't on in Britain yet, sulked for a bit, flicked over to Sky1, found it, and another obsession follwed...